How does a PCP pump work?

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A PCP (Pre-Charged Pneumatic) pump is used to fill the air reservoir of PCP airguns, which are a type of air rifle or air pistol that operates using compressed air instead of gunpowder. Here's how a PCP pump works:

Air Reservoir: PCP airguns have a built-in air reservoir or cylinder. This reservoir is empty or partially filled with air when you start.

Connection: To fill the reservoir, you need a PCP pump. The pump typically has a hose or a connection point that attaches to the air inlet valve on the gun.

Manual Pumping: The PCP pump works like a bicycle pump but is designed to handle much higher pressures. To fill the air reservoir, you manually pump the handle of the PCP pump.

Pressure Gauge: Most PCP pumps have a pressure gauge that displays the pressure being generated as you pump. You need to monitor this gauge to ensure you don't overfill the reservoir, as it could damage the gun.

Air Compression: As you pump the handle, it forces air from the pump into the air reservoir of the PCP gun. The pressure inside the reservoir increases with each pump.

Monitoring Pressure: You'll want to stop pumping when the pressure in the reservoir reaches the desired level, which is usually specified by the manufacturer. Over-pressurizing can be dangerous and can damage the gun.

Safety Measures: PCP pumps often have safety features, such as pressure relief valves, to prevent over-pressurization or to release excess pressure.

Disconnect and Use: Once the air reservoir is adequately pressurized, you disconnect the pump from the gun. The gun is now ready to be used. The number of shots you can get from a full reservoir depends on the gun's design, caliber, and pressure.

It's important to note that PCP pumps can require significant effort to reach high pressures, especially as the reservoir nears its capacity. Some PCP enthusiasts prefer using a high-pressure air tank or compressor to fill their guns because it's more convenient and less physically demanding. However, PCP pumps remain a reliable and portable option for filling PCP airgun reservoirs when other methods are not available.